Protech03...
Stock coil/shock assembly + "preload" spacer = stock travel, installed coil length reduced by spacer thickness (not overall thickness but actual preload portion of design thickness), spring stiffness increased somewhat due to preload increase, stock overall assembly length, percentage of travel from "at rest" goes toward the full extension end by the preload thickness amount or more.

Stock overall assembly length, doesn't it have to be longer in order to have lift? I consider the assembly from the bottom of the shock to the top of the plate that is held on by the nut on the shock piston. i.e. The way it is when removed from the truck.

percentage of travel from "at rest" goes toward the full extension end by the preload thickness amount or more.

Is this the shock piston extended upward,"at rest", by the spacer thickness? Would this not make the assembly longer?
Now remember this is not an argument or anything like that.

 

Call me at 916-220-2137

Late!
Brian

 

strut assembly is already at maximum length with stock spring and no spacer, the spring preload strut would just sag less under the weight of the truck. PS Dgdee, thanks for all the torque specs on the spacer installations

 

Brian at PROTECH - Thank you so much for taking your time and talking to me on the phone about your lift kit. Truly appreciate it!

 

Hello Scottb1014,

No problem...My pleasure! You had some great questions and I am looking into the rear lift options. I have found nothing so far...specific to the new style 04 F150.

Take Care,
Brian at www.ProtechEZLift.com

 

04abqscrew..... here's your quote "same overall length as stock, but the spring has already been partially compressed so it resists compressing much more, it would say only compress another 1" with the weight of the truck on it while a stock spring without spacer would compress 3" with the weight of the truck on it."

O.K. you're on the right track here. When the assembly was out of the truck the shock is fully extended, right?. So you have to compress the spring down 2" to get the 2" spacer to fit. The shock is still fully extended, but the spring is 2" compressed(preloaded). Now put the weight of the truck on the assembly and the truck will compress the spring another 1", for a grand total of 3" of spring compression. Isn't that the same amount as stock? But now, remember The shock was fully extended when we started, but the weight of the truck only retracted/compressed the shock 1". Guess what, you just lost 2" of shock extension. But the overall length of the assembly is 2" longer than stock, thats your lift. The overall length of the coil spring has not changed. Downward compression of a spring determines stiffness. You said it yourself, the coil spring is compressed the same as stock(with the weight of the truck on it, i.e. installed on the truck). So how can it be any stiffer?
Go out and jack your truck up, the assembly gets longer the higher you jack it up.
The disadvantage of preload spacers is you lose shock travel and the shock now travels out of its designed neutral area.
If you're trying to sell a product, only tell how great it is. "Caveat emptor"
Remember, this isn't an argument.

 

thats the drawback to preload spacers versus topload, they give a stiffer ride and also decrease suspension travel, try putting a 2" preload spacer in your springpack you'll see the spring is compressed more even with the weight of the truck on it and will ride stiffer(from personal experience) thats why I went with the topload, but now I find out there's clearance problems with a full 3" lift. thanks for all your input.

 

As stated earlier...Both designs have their limitations.

Too much preload spacer = harsh ride and top out feeling.

Too much top load spacer = binding CV, ball joints, nuckle hits coil spring etc. AKA...BAD STUFF!

Our findings after extensive R&D:

Best for about 2.0" of lift = 1" preload + .25" top spacer
Best for about 2.5" of lift = 1.25" preload + .25" top spacer
Best for about 2.75" of lift = 1.25" preload + .40" top spacer
Best for about 3.0" of lift = 1.35" preload + .50" top spacer

NOTE: Preload thickness does not = actual height increase.
NOTE: Top spacer thickness does not = actual height increase.
This is do to the geometry of the control arms in relation to the shock mounting location.

All of these combinations work very well, and with no illeffects at all. You could come up with many other combinations for slightly firmer or softer ride or height increase using these same parts.

Take Care,
Brian at www.ProtechEZLift.com

 

Put it on the DS 2.5 last weekend drives great! Now the only issue is what tire would fit on the 18" FX4 wheels? Anyone have BFG AT's on theres? Looks good???

 

got my daystar on today. this totally changed the looks of this truck. when i look in my mirrors, i don't see my backend sticking up. the truck just looks much better level. can someone tell me how to post a picture?

 

Just got my protech 2.5" lift today and the kit looks AWESOME. You have to see to believe. Solid, heavy billet material as opposed to poly that may compress or break down, like bushings do, over time. Will look like a stock installation when completed. Can't wait until next week to install, but that is the soonest the shop can fit me in. Thanks Brian, for your patience with the tech assist during my "learning curve". I've really started to understand more of the science and geometry that goes into this overlooked aspect of lifting a vehicle. A true professional.

 

Thanks for the kind words! I knew you would like it. LOL!!!

Please post pictures after the lift install is completed so everyone can see how good it looks.

Take Care,
Brian at www.ProtechEZLift.com

 

Are the 1.25" preload and .25" top-load leveling kits available yet? I know you were doing some additional R&D, but I'd like to purchase one if you've got them ready.

 

Ok, this may be a stupid question but I haven't gotten mine yet. Why is everyone putting on front lifts? Do the trucks look that bad stock? I haven't pay that close attention to it.

 

Most folks, myself included, don't like the looks of the rear sticking up in the air, and rather than lower the rear, I'd like to raise the front.